On 26 October 1623 she married in Zerbst with Duke August the Younger of Brunswick-Wolfenbüttel (1579–1666). This was August's second marriage. His first marriage had remained childless, like that of his brother Julius Ernest. With the birth of her sons, Dorothea thus became the ancestress of the "New House of Brunswick", which went extinct in 1873.[1] The family tree of the Duchess, as of 1617, can still be found in the library in Wolfenbüttel.[2]